The present invention relates generally to a real image type zoom finder and an imaging system that incorporates the same, and more specifically to a real image type zoom finder fit for film-loaded cameras, digital cameras, etc. and an imaging system that incorporates such a real image type zoom finder.
Among lens arrangements so for known to obtain zoom finders of the small, thin yet high-zoom-ratio type, there is a lens arrangement comprising, in order from its object side, a negative lens group, a positive lens group, a negative lens group and a positive lens group, wherein zooming is performed by movement of the second and third lens groups.
In recent years, demands for more compact, higher-zoom-ratio zoom finders have been increasingly growing. Typical such prior art constructions are set forth in the following patent publications.
Patent Publication 1
JP-A 8-136806
Patent Publication 2
JP-A 10-319320
Patent Publication 3
JP-A 2000-347101
Patent Publication 4
JP-A 2001-343585
Although these zoom finders of the real image type are small and thin to some degrees or have a high zoom ratio of the order of about 3.5, yet it is difficult to ensure satisfactory zoom ratios when further size reductions are in demand.